Systems and methods for thermal radiation detection

ABSTRACT

Systems and methods for thermal radiation detection utilizing a thermal radiation detection system are provided. The thermal radiation detection system includes one or more mercury-cadmium-telluride (HgCdTe)-based photodiode infrared detectors or Indium Antimonide (InSb)-based photodiode infrared detectors and a temperature sensing circuit. The temperature sensing circuit is configured to generate signals correlated to the temperatures of one or more of the plurality of infrared sensor elements. The thermal radiation detection system also includes a signal processing circuit.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation-in-part of, and claims priority under35 U.S.C. §120 to, U.S. patent application Ser. No. 17/029,103, filed onSep. 23, 2020, which claims the benefit, under 35 USC 119(e), to U.S.Provisional Patent Application No. 62/906,782, filed on Sep. 27, 2019;both of which are herein incorporated by reference in their entirety.

FIELD OF THE INVENTION

The present disclosure relates to systems and methods for inspectingmanufacturing processes, and more particularly, systems and methods forinspecting manufacturing processes using high-speed thermal radiationdetection.

BACKGROUND OF THE INVENTION

Along an assembly line, absorbent articles may be assembled by addingcomponents to and otherwise modifying an advancing, continuous web ofmaterial. For example, in some processes, advancing webs of material arecombined with other advancing webs of material. In other examples,individual components created from advancing webs of material arecombined with advancing webs of material, which in turn, are thencombined with other advancing webs of material. Webs of material andcomponent parts used to manufacture absorbent articles, such as diapers,may include: backsheets, topsheets, absorbent cores, front and/or backears, fastener components, and various types of elastic webs andcomponents such as leg elastics, barrier leg cuff elastics, and waistelastics. Once the desired component parts are assembled, the advancingweb(s) and component parts are subjected to a final knife cut toseparate the web(s) into discrete diapers or other absorbent articles.The discrete diapers or other absorbent articles may also then be foldedand packaged.

For quality control purposes, absorbent article converting lines,packaging lines, or industrial automation machinery or processes mayutilize various types of sensor technology to inspect the webs anddiscrete components added, transformed, or manipulated within theprocess. Example sensor technology may include vision systems,photoelectric sensors, proximity sensors, laser or sonic distancedetectors, and the like. Product inspection data from the sensors may becommunicated to a controller in various ways. In turn, the controllermay be programmed to receive product inspection data, and in turn, makeadjustments to the manufacturing process. In some instances, thecontroller may reject defective absorbent articles based on the productinspection data after the final knife cut at the end of the convertingline.

In addition, manufacturing processes may utilize various types of sensortechnology to monitor the performance of various types of assemblyequipment used in the industrial process. Example process sensortechnology may include speed sensors, linear or radial position sensors,temperature, pressure or vacuum sensors, vision systems, proximitysensors, and the like. Process data from the process sensors may becommunicated to a controller in various ways. In turn, the controllermay be programmed to receive process data, and in turn, make adjustmentsto the manufacturing process and/or communicate potential problemsassociated with assembly equipment to technicians or operators. In someinstances, based on the process data, the controller may automaticallyshutdown the process.

Some absorbent article converting lines, assembly processes, industrialprocesses, or equipment may utilize infrared sensors to monitorperformance, or otherwise provide operational feedback regarding thewebs, discrete components, or other equipment or processes. There arethermal type infrared sensors (e.g., pyroelectric elements orthermopiles) that employ temperature changes generated by the absorptionof infrared energy, and quantum type infrared sensors that employchanges in conductivity, or in electromotive force, voltage, or current,that are generated by electrons excited by incident photons. The thermaltype, however, which can be operated at room temperature, hasdisadvantages in that it requires broad-band wavelength exposure(typically more than 4 microns) and a low sensitivity and in that itsresponse speed is slow. Due to the low sensitivity and slow responsespeed, these type of sensors are not typically adequate for use inmonitoring higher speed manufacturing processes. On the other hand, thequantum type, although it must be cooled to extremely low temperatures,has characteristics such as requiring less broad-band wavelengthexposure (typically less than 4 microns) and high sensitivity and highresponse speed. Many quantum type sensors must be cooled using liquidnitrogen or liquid helium or by using electronic cooling, such as usinga Stirling cooler for example, in order to provide reduce nose andachieve the desired sensitivity. In some instances, these types ofsensors must be cooled to about −200° Celsius. Cooling the entire sensorrequires the overall form factor to be increased, and accordingly, makesit challenging, if not impractical, to incorporate such sensors intosmall spaces. In many cases, positioning such sensors proximate to amanufacturing system to verify a manufacturing process via an infraredsignal is not feasible due to the confines of the surrounding machinery,in addition to other limitations. The cooling requirements require moreenergy in addition to space. The cooling components consume additionalpower, and in turn, generate additional thermal noise which must bedirected, contained, or transported away. Therefore, there is a need forsystems and methods for providing infrared sensing for manufacturingsystems with the sensing have the desired response speed and formfactor.

For some non-industrial applications, such as vehicle, pedestrian, orobject collision avoidance, detection, tracking, or monitoring; someapplications require sensors which are both fast and able to operate atambient temperature. The cooling requirements for such applicationsprohibits practicality for many of the same reasons as industrialapplications, namely cost, speed, size, and power consumption.

SUMMARY OF THE INVENTION

In one form, a thermal radiation detection system comprises a pluralityof infrared sensor elements arranged as an array, wherein each of theplurality of infrared sensor elements comprises a semiconductor selectedfrom a mercury-cadmium-telluride (HgCdTe)-based photodiode infrareddetector, or an Indium Antimonide (InSb)-based photodiode infrareddetector, configured to generate an output responsive to detectedmid-infrared wavelengths. The thermal radiation detection system mayalso comprises an amplifier circuit, the amplifier circuit beingconfigured to convert the current outputs from the plurality of infraredsensor elements to output voltages. The thermal radiation detectionsystem also comprises a temperature sensing circuit, the temperaturesensing circuit being configured to generate signals correlated totemperatures of one or more of the plurality of infrared sensorelements. The thermal radiation detection system also comprises a signalprocessing circuit, the signal processing circuit configured to generatea signal usable by an imaging system based on the signals generated bythe temperature sensing circuit and the output voltages from theamplifier circuit or infrared sensor elements. The signals generated bythe temperature sensing circuit is used to correct for noise or driftfrom the signals generated by the infrared sensor elements or theirassociated amplifier. The correction can be a linear or non-linearcorrection, depending on the characterization of signals. In someembodiments, the corrections are look up tables corresponding to knownexperimental or historical conditions.

The electrodes connected to the infrared sensor elements are arrangedsuch that the connections are not on the same surface as the incidentinfrared energy allowing a larger proportion of the surface to receiveenergy unimpeded by connection terminals. The larger proportion of theexposed surface increases the efficiency and signal-to-noise rations andtherefore improving the speed and sensitivity of the detection elements.

The improved signal-to-noise ratio of the infrared sensor elementsallows the system to be operated at ambient temperature. Ambienttemperature for some field conditions would be above 0° C. and below 55°C. Preferably ambient temperature is defined as between 5° C. and 25° C.The ambient temperature for some field conditions may be raised due toproximity to other items such as motors, heaters, CPUs, or generators.The ambient temperature for some field conditions may be lowered due toproximity to other items such forced or entrained fluid or air movement.

In another form, a thermal radiation detection system comprises a firstmercury-cadmium-telluride (HgCdTe)-based or an Indium Antimonide(InSb)-based photodiode infrared detector configured to generate a firstoutput responsive to detected infrared wavelengths and a firsttransimpedance amplifier to convert the current output from the firstHgCdTe-based or InAs-based photodiode infrared detector to an outputvoltage. The thermal radiation detection system also comprises a firsttemperature sensing device positioned proximate to the firstHgCdTe-based or InAs-based photodiode infrared detector, the firsttemperature sensing device to generate a signal correlated totemperature. The thermal radiation detection system also comprises asignal processing circuit, the signal processing circuit configured togenerate a signal based on the signal generated by the first temperaturesensing circuit and the output voltage from the first transimpedanceamplifier.

In another form, a method for inspecting an article manufacturingprocess comprises positioning a thermal radiation detection systemproximate to a manufacturing process, advancing an article past theplurality of infrared sensor elements subsequent to the manufacturingprocess, and identifying characteristics of the manufacturing processbased on the signal from the signal processing circuit.

BRIEF DESCRIPTION OF THE DRAWINGS

The above-mentioned and other features and advantages of the presentdisclosure, and the manner of attaining them, will become more apparent,and the disclosure itself will be better understood, by reference to thefollowing description of non-limiting embodiments of the disclosuretaken in conjunction with the accompanying drawings, wherein:

FIG. 1 schematically depicts a thermal radiation detection system inaccordance with an example embodiment.

FIG. 2 schematically depicts another thermal radiation detection systemin accordance with an example embodiment.

FIG. 3 provides a simplified view of an infrared sensor element inaccordance with an example embodiment.

FIG. 4 depicts a portion of an example thermal radiation detectionsystem.

FIG. 5 schematically depicts a thermal radiation detection system havingan array of infrared sensor elements.

FIG. 6 schematically depicts a thermal radiation detection system havingan array of infrared sensor elements.

FIG. 7 schematically illustrates the placement of a plurality of arrays,each of which comprises infrared sensor elements arranged linearly.

FIG. 8 is a simplified isometric view of an article moving in a machinedirection (MD) relative to a linear array of infrared sensor elements.

FIG. 9 is a simplified isometric view of another article moving in amachine direction (MD) relative to a plurality of linear arrays, each ofwhich includes a plurality of infrared sensor elements.

FIG. 10 schematically depicts a simplified manufacturing processincorporating an example thermal radiation detection system.

FIG. 11 is a simplified thermal radiation detection system that isconfigured as a spectroscopy sensor device.

DETAILED DESCRIPTION OF THE INVENTION

The present disclosure relates to high speed infrared sensor systems andmethods thereof. Various nonlimiting embodiments of the presentdisclosure will now be described to provide an overall understanding ofthe principles of the function, design and operation of the systems andmethods. One or more examples of these nonlimiting embodiments areillustrated in the accompanying drawings. Those of ordinary skill in theart will understand that the systems and methods described herein andillustrated in the accompanying drawings are nonlimiting exampleembodiments and that the scope of the various nonlimiting embodiments ofthe present disclosure are defined solely by the claims. The featuresillustrated or described in connection with one nonlimiting embodimentmay be combined with the features of other nonlimiting embodiments. Suchmodifications and variations are intended to be included within thescope of the present disclosure.

FIG. 1 schematically depicts a thermal radiation detection system 100 inaccordance with an example embodiment. Various components of the thermalradiation detection system 100 can be positioned proximate to an article112 in order to detect incident infrared radiation, schematicallydepicted as infrared radiation 114. The article 112 can comprise, forexample, any of a web, a substrate, a bottle, a package, a component ofmachinery, an elastic, an adhesive, an absorbent gelling material (AGM),a printing, a chemical additive, a lotion, and a volatile composition.The infrared radiation 114 can be used to assess the quality or othercharacteristic of a manufacturing process, such as an application of anadhesive to the article 112, seaming of the article 112, heat bondingthe article 112, pressure welding the article 112, cohesive bonding thearticle 112, and so forth.

The thermal radiation detection system 100 can include at least oneinfrared sensor element 104 that is positioned proximate to atemperature sensor 106. The temperature sensor 106 can be any suitablesensing device, such as a negative temperature coefficient thermistor, athermocouple, a photodiode sensitive to infrared energy, or a resistancetemperature detector, for example. Responsive to the detected infraredradiation 114, the infrared sensor element 104 can provide an output toan amplifier 102. The amplifier 102 can convert the current output fromthe infrared sensor element 104 to an output voltage. The amplifier 102can be any suitable application, and in some embodiments, is implementedas a transimpedance amplifier (TIA).

A signal processing circuit 108 can receive the output voltage from theamplifier 102 along with a signal from the temperature sensor 106. Thesignal processing circuit 108 can, in turn, generate an output signal110 that can be usable by an imaging system, or other suitable system.In some embodiments, the signal processing circuit 108 is anapplication-specific integrated circuit (ASIC), a field programmablegate array (FPGA), a central processing unit (CPU), or a graphicsprocessing unit (GPU). In some embodiments, the signal processingcircuit 108 is a virtualized ASIC, FPGA, CPU, or GPU on a network,internet cloud, or other virtualized computing platform.

The amplifier 102 may be integrated with the signal processing circuit108 or may be after the signal processing circuit 108.

The infrared sensor element 104 can comprise photodiode infrareddetector comprising a semiconductor, wherein the semiconductor isselected from mercury-cadmium-telluride also referred to as an MCT, orindium antimonide or combinations thereof. The infrared sensor elementcan comprise a mercury-cadmium-telluride (HgCdTe)-based photodiodeinfrared detector, or an Indium Antimonide (InSb)-based photodiodeinfrared detector, that is configured to generate an output responsiveto detected infrared wavelengths. Such detected wavelengths of infraredradiation can be usable for inspection purposes, quality control, and soforth. In some embodiments, the detected infrared wavelengths are about4 microns to about 14 microns, for example, specifically reciting all0.5 micron increments within the above-recited range and all rangesformed therein or thereby. The temperature sensor 106 can be a componentof a temperature sensing circuit of the thermal radiation detectionsystem 100. As the output generated by the infrared sensor element 104can be dependent on operational temperature, the temperature sensingcircuit can be configured to generate a signal that correlates to thetemperature of the infrared sensor element 104.

FIG. 2 schematically depicts another thermal radiation detection system200 in accordance with an example embodiment. This thermal radiationdetection system 200 is similar to the thermal radiation detectionsystem 100, as it includes at least one infrared sensor element 204 thatis positioned proximate to a temperature sensor 206. Responsive todetected infrared radiation 214 from an article 212, the infrared sensorelement 204 can provide an output to an amplifier 202. The amplifier 202can convert the current output from the infrared sensor element 204 toan output voltage. A signal processing circuit 208 can receive theoutput voltage from the amplifier 202 along with a signal from thetemperature sensor 206. The signal processing circuit 208 can, in turn,generate an output signal 210 that can be usable by an imaging system,or other suitable system.

In this embodiment, however, the thermal radiation detection system 200includes a cooling circuit that includes a thermoelectric cooler 216that is positioned proximate to the infrared sensor element 204. Thethermoelectric cooler 216 can be configured to generally regulate anoperational temperature of the infrared sensor element 204. Inaccordance with various implementations, the thermoelectric cooler 216is configured to regulate the operational temperature of the infraredsensor element 204 to within a range of about 5° C. to about 40° C.,specifically reciting all 1° C. increments within the above-recitedrange and all ranges formed therein or thereby. In some implementations,the thermoelectric cooler 216 is configured to regulate the operationaltemperature of the infrared sensor element 204 to a range of about 15°C. to about 24° C., specifically reciting all 1° C. increments withinthe above-recited range and all ranges formed therein or thereby.

As the signals generated by the infrared sensor element 204 can betemperature dependent, including a cooling circuit in the thermalradiation detection system 200 can help to control and limit feedbackrunaway and to maintain certain operational conditions for the infraredsensor element 204. Other cooling mechanisms may be implemented toaccomplish the same result such as fan cooling or heat sinks, forexample.

FIG. 3 provides a simplified view of an infrared sensor element 304 inaccordance with an example embodiment. The infrared sensor element 304can be a component of a thermal radiation detection system 300, forexample. The infrared sensor element 304 can include a plurality oflayers, including a semi-insulating Gallium arsenide (GaAs) substrate,in a plan view. A first electrode 320 can be electrically coupled to afirst of the plurality of layers and a second electrode 322 can beelectrically coupled to a second of the plurality of layers. Thedetected infrared wavelengths from an article 312, schematically shownas infrared radiation 314, are transmitted through the GaAs substrate tothe first and second electrodes 320 and 322. Notably, the first andsecond electrodes 320 and 322 are not positioned on the same surfacethat is receiving the infrared radiation 314 from the article 312. Thisplacement of the first and second electrodes 320 and 322 beneficiallyprevents them from interrupting or masking the infrared sensor, therebycreating a larger surface area for collecting the infrared radiation 314and contributing to quick spectral response. Suitable alternatives toGallium arsenide are Indium gallium arsenide (InGaAs, extended-InGaAs),or Germanium (Ge).

While FIGS. 1 and 2 depict single infrared sensor elements 104 and 204for the purposes of illustration, in some embodiments a thermalradiation detection system can include an array of infrared sensorelements. FIG. 4 depicts a portion of a thermal radiation detectionsystem 400 that includes an array of infrared sensor elements. While twoinfrared sensor elements 404A and 404B are shown for the purposes ofillustration in FIG. 4 , it is to be appreciated that the array caninclude any suitable number of infrared sensor elements. In someconfigurations, the array is sized such that it extends in a crossdirection (CD) relative to an article 412 to detect infrared radiation414 across substantially the entire width of the article 412. The arraycould as well be implemented to extend across only a portion of anarticle 412 to acquire representative signals without the need to extendacross the entire article. As shown in FIG. 4 , various components ofthe thermal radiation detection system 400 can be bonded to othercomponents, such as through thermally conductive adhesives. In thisregard, the infrared sensor element 404A is shown bonded to atemperature sensor 406A, an amplifier 402A, and a cooling circuit 416A.Similarly, the infrared sensor element 404B is shown bonded to atemperature sensor 406B, an amplifier 402B, and a cooling circuit 416B.While FIG. 4 depicts a one-to-one arrangement with regard to infraredsensor elements and the temperature sensor and the cooling circuit, thisdisclosure is not so limited. In other embodiments, as shown FIGS. 5 and6 , for example, the temperature sensor and the cooling circuit may havea one-to-many arrangement with regard to infrared sensor elements.

FIG. 5 schematically depicts a thermal radiation detection system 500having an array of infrared sensor elements 504A-D. While four infraredsensor elements 504A-D are shown for the purposes of illustration, thethermal radiation detection system 500 can include any suitable numberof infrared sensor elements, as indicated by the infrared sensorelements shown in dashed lines. The array of infrared sensor elements504A-D can be arranged such that it generally extends in a crossdirection (CD) across an article 512 to detect infrared radiation 514.In this embodiment, each infrared sensor element 504A-D is configured toprovide an output signal to a respective amplifier 502A-D. Each of theamplifiers 502A-D is configured to provide its output to a signalprocessing circuit 530. Additionally, temperature sensors 506A and 506Bare configured to provide signals to the signal processing circuit 530responsive to the sensed temperature proximate to one or more of theinfrared sensor elements 504A-D. In the illustrated embodiment, thetemperature sensor 506A provides temperature information for infraredsensor elements 504A and 504B, and the temperature sensor 506B providestemperature information for infrared sensor elements 504C and 504D. Asis to be appreciated, however, other arrangements can be used withoutdeparting from the scope of the present disclosure. Responsive to thesignals received from the amplifiers 502A-D and the temperature sensors506A and 506B, the signal processing circuit 530 can provide an outputto an image system 532, or other suitable system.

FIG. 6 schematically depicts a thermal radiation detection system 600having an array of infrared sensor elements 604A-D. While four infraredsensor elements 604A-D are shown for the purposes of illustration, thethermal radiation detection system 600 can include any suitable numberof infrared sensor elements. The array of infrared sensor elements604A-D can be arranged such that it generally extends in a crossdirection (CD) across an article 612 to detect infrared radiation 614.In this embodiment, each infrared sensor elements 604A-D is configuredto provide an output signal to a respective amplifier 602A-D. Each ofthe amplifiers 602A-D is configured to provide its output to a signalprocessing circuit 630. In this embodiment, temperature sensors606A-606D are thermally bonded to respective infrared sensor elements604A-D. The temperature sensors 606A-606D are configured to providesignals to the signal processing circuit 630 responsive to the sensedtemperature proximate to the infrared sensor elements 604A-D. Thethermal radiation detection system 600 also includes thermoelectriccoolers 616A-616C. The thermoelectric coolers 616A-616C are operative toregulate the operational temperature of the infrared sensor elements604A-D to within a range of about 5° C. to about 40° C., for example,specifically reciting all 1° C. increments within the above-recitedrange and all ranges formed therein or thereby. Responsive to thesignals received from the amplifiers 602A-D and the temperature sensors606A-606D, the signal processing circuit 630 can provide an output to animage system 632, or other suitable system.

FIG. 7 schematically illustrates the placement of a plurality of arrays770A-770D, each of which comprise infrared sensor elements arrangedlinearly. As shown, the illustrated portion of the array 770A includesinfrared sensor element 704A, the array 770B includes infrared sensorelements 704B-704F, the array 770C includes infrared sensor elements704G-704K, and the array 770D includes infrared sensor elements 704L-M.The arrays 770A-770D can be modular, such that any suitable number ofarrays can be placed side by side to provide the desired width. Asshown, each infrared sensor element with an array is equally spaced fromadjacently infrared sensor elements, as shown by distance “D”.Furthermore, the distance “D” is also maintained between the outermostinfrared sensor elements of adjacently positioned arrays. By way ofexample, the infrared sensor element 704A of the array 770A is separatedby a distance of “D” from the infrared sensor element 704B of the array770B. Thus, from a data collection perspective, the imaging in a crossdirection (CD) can be generally uniform across the entire article, evenif a plurality of arrays of infrared sensor elements are placed side byside. Further, while the width of the arrays can vary (shown as W1 andW2 in FIG. 7 ), in some embodiments the width of the array is in therange of 10 mm to 200 mm In some embodiments, each of the arrays has awidth of 100 mm.

FIG. 8 is a simplified isometric view of an article 812 moving in amachine direction (MD) relative to an array 870 of infrared sensorelements 804 and in close proximity to article 812 as is typical of acontact image sensor (CIS) or linescan application. In one embodiment,close proximity of no more than 10 cm from an article 812 ensures thatthe space requirements for the array 870 is minimized In anotherembodiment, close proximity of no more than 30 cm from an article 812ensures that the infrared energy focuses on minimum number of sensingelements 804 at a time. Ideally the infrared energy from any point onarticle 812 is incident on only a single sensing element 804. In someembodiments, the infrared energy from any point on article 812 may beincident on a plurality of sensing elements 804 when the cross machinedirection resolution is of less importance. As shown, the infraredsensor elements 804 are linearly positioned such that they collectinfrared radiation from a scan area 872. Depending on the article 812and the width of the array 870, the scan area 872 can generally extendacross the entire article 812, or a portion of the article 812. FIG. 9is a simplified isometric view of an article 912 moving in a machinedirection (MD) relative to a plurality of arrays 970A and 970B, each ofwhich includes a plurality of infrared sensor elements 904. Bypositioning the arrays 970A and 970B side by side, they can collectinfrared radiation from a scan area 972 that generally extends acrossthe entire article 912, or a portion of the article 912.

Thermal radiation detection systems in accordance with the presentdisclosure can beneficially be deployed at positions along amanufacturing process, including positions that are relatively confined.FIG. 10 schematically depicts a simplified manufacturing processincorporating a thermal radiation detection system 1000. While themanufacturing process depicted in FIG. 10 is a converting process forwebs of materials, it is to be appreciated that the thermal radiationdetection system can be used with a wide variety of different type ofmanufacturing processes. Thus, while webs are shown as the article ofmanufacture in FIG. 10 , in other embodiments the web can be any of, forexample, a substrate, a bottle, a package, a component of machinery, anelastic, an adhesive, an absorbent gelling material (AGM), a printing, achemical additive, a lotion, and a volatile composition. Further, whileFIG. 10 schematically depicts joining webs with an adhesive, othermanufacturing process that can utilize thermal radiation detectionsystems in accordance with the present disclosure include processing forseaming the article, heat bonding the article, pressure welding thearticle, cohesive bonding the article, and so forth.

A first web of material 1056 and a second web of material 1060 are shownbeing joined by an adhesive 1054 dispensed from an applicator 1052. Dueto the orientation of the rollers 1058, as well as other components asmay be required, the available area to place an array 1070 of infraredsensor elements which is downstream of the applicator 1052 is quiteconfined. Nevertheless, due to the configuration of the thermalradiation detection system 1000, the array 1070 can be placedappropriately to receive infrared radiation 1014 from an article 1012.While not shown in FIG. 10 , it is to be appreciated that one or moretemperature sensors can also be associated with the array 1070. In someconfigurations, one or more thermoelectric coolers, or other types ofcooling systems, can also be associated with the array 1070. A signalprocessing circuit 1030 can receive signaling based on the infraredradiation 1014 and the temperature of the infrared sensor elements inthe array 1070. The signal processing circuit 1030 can be any of anapplication-specific integrated circuit, a field programmable gatearray, a central processing unit, and a graphics processing unit, forexample. An output 1010 of the signal processing circuit 1030 can beuseable by, for example, a data acquisition system, an industrialcomputer control system, an imaging system, among a variety of othersystems or processes.

Furthermore, a thermal radiation detection system in accordance with thepresent disclosure can be configured to function as a spectroscopysensor. FIG. 11 is simplified thermal radiation detection system thatcomprises a plurality of infrared sensor elements 1104A-1104E that arepositioned to receive incident radiation 1114 from an article 1112.Similar to previously described embodiments, one or more temperaturesensors, amplifiers, and optionally one or more thermoelectric coolers,can be associated with the infrared sensor elements 1104A-1104E. A firstnotch filter 1130 can be positioned proximate to a first infrared sensorelement 1104A and a second notch filter 1140 can be positioned proximateto a second infrared sensor element 1104D. As schematically shown in thespectral response chart 1180, the notch filters 1130 and 1140 allow forthe analysis of the spectral response in particular bands. By way ofexample, a first infrared sensor element 1104A allows for the analysisof the spectral response in a first band 1186 and the second infraredsensor element 1104D allows for the analysis of the spectral response ina second band 1188. As such, the spectral response of a first material1182 in each of the first and second bands 1186 and 1188 can be comparedto the spectral response of a second material 1184 in each of the firstand second bands 1186 and 1188. Using these comparisons, certaindeterminations regarding the first and second materials 1182 and 1184can be made. For example, if the spectral response is high in the firstband 1186 and low in the second band 1188, it could indicate thematerial is an absorbent gelling material (AGM). Comparatively, if thespectral response is low in the first band 1186 and high in the secondband 1188, it could indicate the material is an adhesive.

Combinations

A. A thermal radiation detection system, comprising:

a plurality of infrared sensor elements arranged as an array, whereineach of the plurality of infrared sensor elements comprises amercury-cadmium-telluride (HgCdTe)-based photodiode infrared detector,or an Indium Antimonide (InSb)-based photodiode infrared detector,configured to generate an output responsive to detected infraredwavelengths;

optionally, an amplifier circuit, the amplifier circuit configured toconvert the current outputs from the plurality of infrared sensorelements to output voltages;

a temperature sensing circuit, the temperature sensing circuitconfigured to generate signals correlated to temperatures of one or moreof the plurality of infrared sensor elements; and

a signal processing circuit, the signal processing circuit configured togenerate a signal usable by an imaging system based on the signalsgenerated by the temperature sensing circuit and the output voltagesfrom the amplifier circuit.

B. The thermal radiation detection system according to Paragraph A,wherein the amplifier circuit comprises a transimpedance amplifier.

C. The thermal radiation detection system according to any of ParagraphsA through B, further comprising a cooling circuit, the cooling circuitconfigured to regulate an operational temperature of the plurality ofinfrared sensor elements.

D. The thermal radiation detection system according to Paragraph C,wherein the cooling circuit comprises a thermoelectric cooler.

E. The thermal radiation detection system according to Paragraph D,wherein the thermoelectric cooler is configured to regulate theoperational temperature of the plurality of infrared sensor elements toa range of about 5° C. to about 40° C.

F. The thermal radiation detection system according to Paragraph E,wherein the thermoelectric cooler is configured to regulate theoperational temperature of the plurality of infrared sensor elements toa range of about 15° C. to about 24° C.

G. The thermal radiation detection system according to any of ParagraphsA through F, wherein the signal processing circuit comprises any of anapplication-specific integrated circuit, a field programmable gatearray, a central processing unit, and a graphics processing unit.H. The thermal radiation detection system according to any of ParagraphsA through G, wherein the temperature sensing circuit comprises one ormore temperature sensing device, wherein the one or more temperaturesensing device is a negative temperature coefficient thermistor, athermocouple, or a resistance temperature detector.I. The thermal radiation detection system according to Paragraph H,wherein each of the plurality of infrared sensor elements is associatedwith a respective transimpedance amplifier and a respective temperaturesensing device.J. The thermal radiation detection system according to Paragraph I,wherein each of the plurality of infrared sensor elements is positionedproximate to a respective negative temperature coefficient thermistor.K. The thermal radiation detection system according to Paragraph J,wherein each of the plurality of infrared sensor elements is bonded tothe respective negative temperature coefficient thermistor.L. The thermal radiation detection system according to any of ParagraphsA through K, comprising a plurality of thermoelectric coolers, whereineach of the plurality of thermoelectric coolers are positioned toregulate the operational temperature of a subset of the plurality ofinfrared sensor elements.M. The thermal radiation detection system according to any of ParagraphsA through L, wherein a width of the array is greater than about 10 cm.N. The thermal radiation detection system according to any of ParagraphsA through M, wherein the array comprises more than 10 infrared sensorelements.O. The thermal radiation detection system according to any of ParagraphsA through N, wherein the plurality of infrared sensor elements arrangedas the array is a first plurality of infrared sensor elements arrangedas a first linear array.P. The thermal radiation detection system according to Paragraph O,further comprising: a second plurality of infrared sensor elementsarranged as a second linear array.Q. The thermal radiation detection system according to Paragraph P,wherein:

each infrared sensor element of the first plurality of infrared sensorelements is equally spaced apart from adjacent infrared sensors in thefirst linear array; and

each infrared sensor element of the second plurality of infrared sensorelements is equally spaced apart from adjacent infrared sensors in thesecond linear array.

R. The thermal radiation detection system according to Paragraph Q,wherein the first linear array is provided as a first modular array andthe second linear array is provided as a second modular array, whereinwhen the first modular array is positioned immediately adjacent to andin-line with the second modular array, an outermost infrared sensorelement of the first linear array is adjacent to an outermost infraredsensor element of the second linear array, and wherein a distance fromthe outermost infrared sensor element of the first linear array to theoutermost infrared sensor element of the second linear array is equal tothe spacing between adjacent infrared sensor elements of both the firstlinear array and the second linear array.S. The thermal radiation detection system of claim R, wherein the firstmodular array has a width greater than about 50 mm and the secondmodular array has a width greater than about 50 mmT. The thermal radiation detection system according to Paragraph S,wherein the first modular array has a width of about 100 mm and thesecond modular array has a width of about 100 mm.U. The thermal radiation detection system according to any of ParagraphsA through T, wherein the detected mid-infrared wavelengths are about 4microns to about 14 microns.V. The thermal radiation detection system according to any of ParagraphsA through U, wherein the mercury-cadmium-telluride (HgCdTe)-basedphotodiode infrared detector or Indium Antimonide (InSb)-basedphotodiode infrared detector comprises:

a plurality of layers comprising a semi-insulating Gallium arsenide(GaAs), Indium gallium arsenide (InGaAs), or Germanium (Ge) substrate ina plan view;

a first electrode electrically coupled to a first of the plurality oflayers and a second electrode electrically coupled to a second of theplurality of layers; and

wherein the detected mid-infrared wavelengths are transmitted throughthe GaAs, Indium gallium arsenide (InGaAs), or Germanium (Ge) substrateto the first and second electrodes.

W. The thermal radiation detection system according to any of ParagraphsA through V, further comprising a first notch filter positionedproximate to a first infrared sensor element of the plurality ofinfrared sensor elements and a second notch filter positioned proximateto a second infrared sensor element of the plurality of infrared sensorelements.X. The thermal radiation detection system according to Paragraph W,wherein the output generated by the first infrared sensor element isresponsive to a first set of wavelengths and the output generated by thesecond infrared sensor element is responsive to a second set ofwavelengths.Y. The thermal radiation detection system according to Paragraph X,wherein the output generated by each of the first and second sensorelements are usable to quantify a spectral response.Z. The thermal radiation detection system according to any of ParagraphsA through Y, further comprising the imaging system.AA. A thermal radiation detection system, comprising:

a first mercury-cadmium-telluride (HgCdTe)-based or Indium Antimonide(InSb)-based photodiode infrared detector configured to generate a firstoutput responsive to detected infrared wavelengths;

optionally, a first transimpedance amplifier to convert the currentoutput from the first HgCdTe-based or (InSb)-based photodiode infrareddetector to an output voltage;

a first temperature sensing device positioned proximate to the firstHgCdTe-based or (InSb)-based photodiode infrared detector, the firsttemperature sensing device to generate a signal correlated totemperature; and

a signal processing circuit, the signal processing circuit configured togenerate a signal based on the signal generated by the first temperaturesensing circuit and the output voltage from the first transimpedanceamplifier.

AB. The thermal radiation detection system according to Paragraph AA,wherein the signal from the signal processing circuit is usable by animage system.

AC. The thermal radiation detection system according to Paragraph AB,further comprising the image system.

AD. The thermal radiation detection system according to any ofParagraphs AA through AC, wherein the signal from the signal processingcircuit is usable by a data acquisition system.

AE. The thermal radiation detection system according to Paragraph AD,further comprising the data acquisition system.

AF. The thermal radiation detection system according to any ofParagraphs AA through AE, wherein the signal from the signal processingcircuit is usable by an industrial computer control system.

AG. The thermal radiation detection system according to Paragraph AF,further comprising the industrial computer control system.

AH. The thermal radiation detection system according to any ofParagraphs AA through AG, further comprising a second HgCdTe-based or(InSb)-based photodiode infrared detector positioned adjacent to thefirst HgCdTe-based or (InSb)-based photodiode infrared detector.AI. The thermal radiation detection system according to Paragraph AH,further comprising:

a second transimpedance amplifier to convert a current output from thesecond HgCdTe-based or (InSb)-based photodiode infrared detector to anoutput voltage;

AJ. The thermal radiation detection system according to Paragraph AI,wherein the first temperature sensing device is positioned proximate tothe second HgCdTe-based or (InSb)-based photodiode infrared detector andwherein the signal processing circuit is to generate a signal based onthe signal generated by the first temperature sensing device and theoutput voltage from the second transimpedance amplifier.AK. The thermal radiation detection system according to Paragraph AI,further comprising a second temperature sensing device positionedproximate to the second HgCdTe-based or (InSb)-based photodiode infrareddetector, the second temperature sensing device to generate a signalcorrelated to temperature.AL. The thermal radiation detection system according to Paragraph AK,wherein the signal processing circuit is configured to generate a signalbased on the signal generated by the second temperature sensing deviceand the output voltage from the second transimpedance amplifier.AM. The thermal radiation detection system according to Paragraph AI,further comprising:

a first thermoelectric cooler positioned proximate to the firstHgCdTe-based or (InSb)-based photodiode infrared detector; and

a second thermoelectric cooler positioned proximate to the secondHgCdTe-based or (InSb)-based photodiode infrared detector.

AN. The thermal radiation detection system according to any ofParagraphs AA through AM, wherein the first temperature sensing deviceis a negative temperature coefficient thermistor, a thermocouple, or aresistance temperature detector.

AO. The thermal radiation detection system according to any ofParagraphs AA through AN, further comprising the imaging system.

AP. A method for inspecting an article manufacturing process, the methodcomprising:

positioning the thermal radiation detection system of Paragraph Aproximate to a manufacturing process;

advancing an article past the plurality of infrared sensor elementssubsequent to the manufacturing process; and

identifying characteristics of the manufacturing process based on thesignal from the signal processing circuit.

AQ. The method according to Paragraph AP, wherein the article comprisesany of a web, a substrate, a bottle, a package, a component ofmachinery, an elastic, an adhesive, an absorbent gelling material (AGM),a printing, a chemical additive, a lotion, and a volatile composition.AR. The method according to any of Paragraphs AO through AQ, wherein themanufacturing process comprises any of an application of an adhesive tothe article, seaming the article, heat bonding the article, pressurewelding the article, and cohesive bonding the article.AS. The method according to any of Paragraphs AO through AR, wherein thethermal radiation imaging system is positioned within 10 cm of a surfaceof the article.AT. The method according to any of Paragraphs AO through AS, wherein thesubstrate is advanced passed the plurality of infrared sensor elementsin a machine direction (MD) at a speed of at least 5 m/s.AU. The method according to any of Paragraphs AO through AT, wherein thethermal radiation imaging system comprises a plurality of modular lineararrays of infrared sensor elements, and wherein the plurality of modularlinear arrays extend in a cross direction (CD) proximate to the article.AV. The method of claim AT, wherein the plurality of modular lineararrays extend at least partially across the article.AW. The method according to any of Paragraphs AO through AV, wherein thethermal radiation detection system is positioned downstream of anadhesive applicator.AX. The method according to any of Paragraphs AO through AW, whereinidentifying the characteristics of the manufacturing process comprisesdetermining a quality of an adhesive application.AY. The method according to any of Paragraphs AO through AX, wherein thethermal radiation imaging system comprises at least two linear arrays ofinfrared sensor elements.

The dimensions and values disclosed herein are not to be understood asbeing strictly limited to the exact numerical values recited. Instead,unless otherwise specified, each such dimension is intended to mean boththe recited value and a functionally equivalent range surrounding thatvalue. For example, a dimension disclosed as “40 mm” is intended to mean“about 40 mm” Every document cited herein, including any crossreferenced or related patent or application and any patent applicationor patent to which this application claims priority or benefit thereof,is hereby incorporated herein by reference in its entirety unlessexpressly excluded or otherwise limited. The citation of any document isnot an admission that it is prior art with respect to any inventiondisclosed or claimed herein or that it alone, or in any combination withany other reference or references, teaches, suggests or discloses anysuch invention. Further, to the extent that any meaning or definition ofa term in this document conflicts with any meaning or definition of thesame term in a document incorporated by reference, the meaning ordefinition assigned to that term in this document shall govern.

While particular embodiments of the present invention have beenillustrated and described, it would be obvious to those skilled in theart that various other changes and modifications can be made withoutdeparting from the spirit and scope of the invention. It is thereforeintended to cover in the appended claims all such changes andmodifications that are within the scope of this invention.

What is claimed is:
 1. A thermal radiation detection system, comprising:a first plurality of infrared sensor elements arranged as a first lineararray, wherein each of the plurality of infrared sensor elementscomprises a semiconductor selected from a mercury-cadmium-telluride(HgCdTe)-based photodiode infrared detector, or an Indium Antimonide(InSb)-based photodiode infrared detector, configured to generate anoutput responsive to detected infrared wavelengths; a second pluralityof infrared sensor elements arranged as a second linear array; atemperature sensing circuit, the temperature sensing circuit configuredto generate signals correlated to temperatures of one or more of theplurality of infrared sensor elements; and a signal processing circuit,the signal processing circuit configured to generate a signal usable byan imaging system based on the signals generated by the temperaturesensing circuit and output based on the infrared sensor elements.
 2. Thethermal radiation detection system of claim 1, further comprising anamplifier circuit, the amplifier circuit configured to convert theoutputs from the first and second plurality of infrared sensor elementsto output voltages, wherein the amplifier circuit comprises atransimpedance amplifier.
 3. The thermal radiation detection system ofclaim 1, further comprising a cooling circuit, the cooling circuitconfigured to regulate an operational temperature of the first andsecond plurality of infrared sensor elements.
 4. The thermal radiationdetection system of claim 3, wherein the cooling circuit comprises athermoelectric cooler.
 5. The thermal radiation detection system ofclaim 4, wherein the thermoelectric cooler is configured to regulate theoperational temperature of the first and second plurality of infraredsensor elements to a range of about 5° C. to about 40° C.
 6. The thermalradiation detection system of claim 5, wherein the thermoelectric cooleris configured to regulate the operational temperature of the first andsecond plurality of infrared sensor elements to a range of about 15° C.to about 24° C.
 7. The thermal radiation detection system of claim 1,wherein the signal processing circuit comprises any of anapplication-specific integrated circuit, a field programmable gatearray, a central processing unit, and a graphics processing unit.
 8. Thethermal radiation detection system of claim 1, wherein the temperaturesensing circuit comprises one or more temperature sensing device,wherein the one or more temperature sensing device is a negativetemperature coefficient thermistor, a thermocouple, an infraredsensitive photodiode, or a resistance temperature detector.
 9. Thethermal radiation detection system of claim 8, wherein each of the firstand second plurality of infrared sensor elements is associated with arespective transimpedance amplifier and a respective temperature sensingdevice.
 10. The thermal radiation detection system of claim 9, whereineach of the first and second plurality of infrared sensor elements ispositioned proximate to a respective temperature sensing element. 11.The thermal radiation detection system of claim 10, wherein each of thefirst and second plurality of infrared sensor elements is bonded to therespective temperature sensing elements.
 12. The thermal radiationdetection system of claim 1, comprising a plurality of thermoelectriccoolers, wherein each of the plurality of thermoelectric coolers ispositioned to regulate the operational temperature of a subset of atleast one of the first and second plurality of infrared sensor elements.13. The thermal radiation detection system of claim 1, wherein a widthof at least one of the first linear array or the second linear array isgreater than about 10 cm.
 14. The thermal radiation detection system ofclaim 1, wherein at least one of the first linear array or the secondlinear array comprises more than 10 infrared sensor elements.
 15. Thethermal radiation detection system of claim 1, wherein: each infraredsensor element of the first plurality of infrared sensor elements isequally spaced apart from adjacent infrared sensors in the first lineararray; and each infrared sensor element of the second plurality ofinfrared sensor elements is equally spaced apart from adjacent infraredsensors in the second linear array.
 16. The thermal radiation detectionsystem of claim 15, wherein the first linear array is provided as afirst modular array and the second linear array is provided as a secondmodular array, wherein when the first modular array is positionedimmediately adjacent to and in-line with the second modular array, anoutermost infrared sensor element of the first linear array is adjacentto an outermost infrared sensor element of the second linear array, andwherein a distance from the outermost infrared sensor element of thefirst linear array to the outermost infrared sensor element of thesecond linear array is equal to the spacing between adjacent infraredsensor elements of both the first linear array and the second lineararray.
 17. The thermal radiation detection system of claim 16, whereinthe first modular array has a width greater than about 50 mm and thesecond modular array has a width greater than about 50 mm.
 18. Thethermal radiation detection system of claim 17, wherein the firstmodular array has a width of about 100 mm and the second modular arrayhas a width of about 100 mm.
 19. The thermal radiation detection systemof claim 1, wherein the detected mid-infrared wavelengths are about 4microns to about 14 microns.
 20. The thermal radiation detection systemof claim 1, wherein the mercury-cadmium-telluride (HgCdTe)-basedphotodiode infrared detector or the InSb-based photodiode infrareddetector comprises: a plurality of layers comprising a semi-insulatingGallium arsenide (GaAs), Indium gallium arsenide (InGaAs) or Germanium(Ge) substrate in a plan view; a first electrode electrically coupled toa first of the plurality of layers and a second electrode electricallycoupled to a second of the plurality of layers; and wherein the detectedmid-infrared wavelengths are transmitted through the GaAs, InGaAs or Gesubstrate to the first and second electrodes.
 21. The thermal radiationdetection system of claim 1, further comprising a first notch filterpositioned proximate to a first infrared sensor element of one of thefirst or the second plurality of infrared sensor elements and a secondnotch filter positioned proximate to a second infrared sensor element ofone of the first or the second plurality of infrared sensor elements.22. The thermal radiation detection system of claim 21, wherein theoutput generated by the first infrared sensor element is responsive to afirst set of wavelengths and the output generated by the second infraredsensor element is responsive to a second set of wavelengths.
 23. Thethermal radiation detection system of claim 22, wherein the outputgenerated by each of the first and second sensor elements are usable toquantify a spectral response.
 24. The thermal radiation detection systemof claim 1, further comprising the imaging system.